Apparatus for adjustably positioning filaments during the manufacture of flat multiconductor cable

ABSTRACT

An apparatus for controllably altering, with time, the lateral spacing or pitch of a number of elongated flexible filaments, preparatory to affixing said filaments to a flexible base material. More specifically, an apparatus for adjustably positioning electrical conductor filaments, before laminating them between two strips of flexible material to form flat multiconductor cable having various lateral spacings or pitches between said conductor filaments. The machine comprises a base structure and a cam assembly which moves relative to the fixed base. A plurality of finger members terminating in filament guides, one such member and guide for each filament, are pivotally attached to the stationary part of the machine. The movable cam assembly serves to govern the positions of and degree of lateral separation between each of the filament guides. A great number of positions and degrees of spreading or separation of the guides, and consequently of the filaments, are possible without alteration or replacement of the cam means. This is accomplished by providing means for altering the velocity and end points of the stroke of the cam means.

United States Patent [72] Inventor Walton Rainey Ardmore, Pa.

[21] Appl. No. 832,581

[22] Filed June 12, 1969 [45] Patented Oct. 26, 1971 [73] Assignee Thomas & Betts Corporation Princeton, NJ.

[54] APPARATUS FOR ADJUSTABLY POSITIONING FILAMENTS DURING THE MANUFACTURE OF FLAT MULTICONDUCTOR CABLE 3,465,432 9/1969 Crimmins 3,481,802 12/1969 Marcel] ABSTRACT: An apparatus for controllably altering, with time, the lateral spacing or pitch of a number of elongated flexible filaments, preparatory to affixing said filaments to a flexible base material. More specifically, an apparatus for adjustably positioning electrical conductor filaments, before laminating them between two strips .of flexible material to form flat multiconductor cable having various lateral spacings or pitches between said conductor filaments. The machine comprises a base structure and a cam assembly which moves relative to the fixed base. A plurality of finger members terminating in filament guides, one such member and guide for each filament, are pivotally attached to the stationary part of the machine. The movable cam assembly serves to govern the positions of and degree of lateral separation between each of the filament guides. A great number of positions and degrees of spreading or separation of the guides, and consequently of the filaments, are possible without alteration or replacement of the cam means. This is accomplished by providing means for altering the velocity and end points of the stroke of the cam means.

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: W4L row RA we)" PATENTEnnc 25 Ian SHEET u 0F 7 APPARATUS FOR ADJUSTABLY POSITIONING FILAMENTS DURING THE MANUFACTURE OF FLAT MULTICONDUCTOR CABLE FIELD OF THE INVENTION This invention relates to an apparatus for varying the position of and/or spacing between a multiplicity of conductor elements being introduced into a laminating machine for making flexible multiconductor flat cables.

DESCRIPTION OF THE PRIOR ART.

Present devices exist for varying the position of or distance between flexible filaments preparatory to positioning them between two moving rolls of flexible strip material during the manufacture of laminated flat multiconductor cables. These machines utilize a number of elongated members pivotallymounted on a stationary portion of the machine. Each elongated member or finger is tipped with a device for guiding a flexible filament prior to the latter being dispensed between the strips of moving flexible material.

A multislotted movable cam provides the means for guiding the elongated fingers for positioning the individual filaments. The fingers each slidably engage one in the movable cam. These cam slots are machined into the cam and configured such that, as the cam is moved, the elongated members pivot, so that the position and/or spacing of each individual filament is altered.

The particular configuration of the cam slots causes the elongated fingers to position the guide devices such that the individual filaments passing through the guides and onto the base material assume a predetermined pattern on that base material when the cam is moved.

It can be seen that the end points of movement of the cam limit the range of positions the filaments can assume on the base material, for a given cam slot configuration.

It is also evident that cam velocity determines the rate of movement of the finger members; it thus, in conjunction with cam slot configuration, determines the angle which the filaments assume across the base material as they are laid upon it during cam movement.

ln prior art devices, the stroke or degree of movement of the cam is fixed and cannot be altered. Therefore, to change the range of positions the filaments may assume on the base material, one must replace the slotted cam.

Furthermore, the cams slots often have intricate configurations. These slots must be designed and machined to extremely close tolerances. Therefore, it is extremely expensive to design and produce new cams. It takes approximately 5 weeks to design a cam plate. Consequently, if a machine could be designed in which one single cam setup would suffice to provide many different ranges and angles of filament lateral position or spacing, it would accomplish a significant saving in expense and setup time.

Since, in the prior art devices, a different cam is necessary for each new range of filament lateral positions or filament angles desired, a number of sets of elongated guide fingers must also be carried in stock. The reason for this is that when a new cam is used, new guide fingers are necessary because the old ones may not cooperate effectively with the new cam which, as noted, must be machined, along with its elongated guide members, to very close tolerances. This is required in that flat conductor cables are presently being manufactured having pitches (or the spacing between conductors) as small as 0.025 inches, and even closer pitches are presently being requested by the electronics packaging industry. Maintaining a large stock of differently sized elongated guide fingers is expensive, and installation of new guide fingers whenever the cam is changed increases the down or lead" time involved in setting up for production.

Up to this point, the prior art devices discussed have been for the production of spread pitch flat conductor cable in which the pitch" between conductors may be varied. Other prior art devices exist for manufacturing fixed pitch flat conductor cable which, as the name implies, is characterized by a uniform pitch between conductors along the length of the cable. Fixed pitch prior art devices include fixed filament guides consisting of round, or half-round, brass bars with slots of appropriate widths and spacing machined therein to define the guides for the conductor filaments. It is obvious that individual fixed filament guides are required for every type of cable structure having a different fixed pitch between conductors. Furthermore, if the proper pitch compensation for shrinkage and thermal effects is not built into the fixed filament guide, it is useless and, thus, a new guide must be made, again at considerable expense.

OBJECTS It is an object of the present invention to provide an apparatus for altering the position of filaments which are being fed into position on a strip of flexible base material, or between two such strips, preparatory to lamination.

Another object of the present invention is to provide an adjustable filament positioning device which is capable, without interchanging cams or filament guides, of varying the ranges of position and angles which the said filaments can assume as they are positioned on the flexible base material.

A further object of the invention is to provide an adjustable filament positioning apparatus having a movable cam as sembly, the velocity and range of motion of which is infinitely adjustable within limits.

A further object of the present invention is to provide an economical and rapid way of setting up a laminating multiconductor cable producing machine for producing a quantity of multiple flat conductor cables.

A further object of the present invention is to provide an adjustable filament positioning apparatus which may be used in the manufacture of fixed-pitch multiconductor cable, and which may function to adjust the pitch between the filaments in order to compensate for shrinkage during a production run and without disturbing the machine setup.

SUMMARY OF THE INVENTION The apparatus of the present invention includes a translatable cam assembly, and a plurality of elongated guide fingers pivotally fastened to a stationary part of the machine. The movable cam assembly consists partially of a pair of flat slotted cams having a number of matching slots on adjacent surfaces. Each of the elongated guide fingers has at some point on its length a drive pin which is adaptable to fit slidably into one matching pair of opposing cam slots. when the cam assembly is translated the filament guides on the tips of the fingers position the filaments on the flexible base material in a certain predictable pattern, depending on the configuration of the cam slots. The cam slots can, for instance, be designed such that the distances between adjacent tips of the guide fingers, and thus between filaments, remain equal at all times, though this distance will, during operation, increase and decrease. An actuator, such as an air or hydraulic cylinder, provides the power for translating the cam assembly.

Means for variably setting the end points of the stroke on the movable cam assembly are provided. The forestroke is limited by adjustable screws mounted on the translatable sec tion, and stops associated therewith fastened to the base portion of the apparatus. The bottoming of the piston of the actuating device acts as a stop for the back stroke of a crosshead member which is attached to the movable cam assembly. The latter can also be rigidly but adjustably positioned at any point, within limits, with respect to the crosshead. This feature enables adjustment of the position assumed by the cam assembly when the air cylinder piston is bottomed. Accordingly, the furthest point of cam assembly backstroke can be fixed.

The velocity of movement of the cam assembly is governable by means of a pair of hydrochecks, each of which is, at one of its ends, attached to the stationary portion of the apparatus, and at the other to the crosshead member. They are connected in a back-to-back" relationship, i.e. one of these hydrochecks limiting velocity in the forward direction, the other in the backward direction.

It can thus be seen that this machine is capable of varying the lateral spacing and/or positioning of separate filaments or wires on a strip base material over a multitude of ranges of distance and angles without substitution of the movable slotted cams.

The prior art devices for attaining ranges of spacing or angles necessitated changing cams. The subject machine substitutes for that alteration by providing for alteration of the end points as well as velocity of the stroke of the cam assembly.

The elongated guide fingers of this machine can be extensively standardized, there being no need for replacement thereof when different positioning is desired, since the intimately associated carn assembly cooperating with the guide fingers is seldom changed. There still remains, however, a necessity for some alteration of this machine when the size of the filaments being positioned is changed substantially. This problem is overcome without the need for substitution of the guide fingers by making each finger with a replaceable tip guide assembly whereby various sized guides could be accommodated on a single finger.

One application for a machine of this type is in the operation of manufacturing laminated fiat multiconductor electrical cable. In this application, the filaments used are of conducting material, such as copper wire. The apparatus, as the wires are dispensed through the filament guides adjustably positions the wires between two strips of flexible insulating material, which composite arrangement is then bonded together in a laminating machine.

DESCRIPTION OF FIGURES The invention will be described further by way of example with reference to the accompanying drawings, wherein:

FIG. 1 is a schematic view of a laminating machine cooperating with the adjustable filament positioner apparatus;

FIG. 2 is a top view of a strip of flat multiconductor cable, the spacing of the conductors of which has been varied with respect to position along its length;

FIG. 3 is a cross section along lines 33 of FIG. 2 of a piece of flat multiconductor laminated cable;

FIG. 8 is a general top view of the adjustable filament positioner;

FIG. 5 is a side view taken in cross section about lines 55 of FIG. 4 of the adjustable filament positioner showing cutaway views of numerous parts;

FIG. 6 is a closeup top view of the movable cam assembly of the adjustable filament positioner;

FIG. 7 is a top view of the adjustable filament positioner showing only selected parts, principally those parts which move relative to the stationary portion of the machine;

FIG. 8 shows a cross-sectional view along lines 88 of FIG. 7 of an elongated guide finger, tipped by a filament guide;

FIG. 9 is a cross-sectional side view along lines 9-9 of FIG. 7 of the principal moving parts of the adjustable filament positioner;

FIG. 10 is a cross-sectional side view along lines 10-10 of F IG. 4 of the trolley structure of the adjustable filament positioner;

FIG. lll illustrates a schematic representation of the centerlines of the conductors W W W of a flat conductor cable, the pitch of which is varied in accordance with the teachings of the subject apparatus;

FIG. 12 schematically illustrates an action diagram of the movement of a guide finger during the transition of the position of a conductor from one pitch spacing to another pitch spacing and FIG. 13 illustrates a vector diagram of the movement of a guide finger during the transition of the conductors of a flat cable from one pitch to a different pitch.

DESCRIPTION OF PREFERRED EMBODIMENTS The primary product designed to be produced utilizing the adjustable filament positioner apparatus is flat multiconductor cable A, a sample of which is shown in FIGS. 2 and 3. This cable is composed of a number of generally parallel electrically conductive filaments or conductors 10 which are sandwiched between flexible plastic material 12. It is often desirable to alter the separation or pitch between the individual conductors of the cable or to impart certain intricate configurations to them. One reason for this is that these flat conductor cables are generally connected at their ends to a number of terminals. To facilitate ease of connection, it is advantageous to cause the filaments to be separated or pitched by a greater distance near the ends of the individual flat conductor strip. The flat conductor cable shown in FIG. 2 is a multipitch conductor, that is, the conductors are separated, depending upon the position on the cable, by varying distances. Between the constant degrees of separation are transition areas generally denoted as regions T. Each wire in this region makes a transfer angle a with a perpendicular to the center line of the base material, as shown in FIG. 2.

Referring to FIG. 1, extending from filament positioner 1, schematically drawn, is a guide finger 37, tipped by filament guide 44. In turn, conductor filament I0 is fed from roller 5, is guided by filament guide 44, and passes between laminating machine rollers 7. Rollers 4 dispense strips of plastic laminating material 12 above and below the conductor filament 10, as the conductor enters the laminating machine.

The laminating machine bonds the whole sandwich as sembly together by means of heater 8 and rollers 70. The processed flat cable A is then wound onto accumulator roll 9.

Bear in mind that, in production of multiconductor cables, there would be not one, but many filaments and guide fingers, rather than the single arrangement shown.

Referring now to FIG. 5, the pitch spreader assembly is mounted upon two trunnions 14 which clamp onto support bar 16. By unclamping trunnions 14, the assembly may be rotated about support bar 16 or moved transversely along this member to any desired position Trunnions 14 are bolted to base plate 18 which supports the pitch spreader assembly.

A precision trolley structure is provided in order to allow linear sliding motion of the movable portion of the apparatus. This trolley mechanism consists partially of a pair of precision ground shafts 20, shown in FIGS. 4 and 10, which are anchored by blocks 21, which blocks are bolted to base plate 18. Bearing blocks 23 are mounted on shafts 20, one pair of bearing blocks to each shaft. As illustrated in FIG. I0, these bearing blocks carry ball bushings 24 of a size adapted to roll on shafts 20 with a minimum of play. Bearing blocks 23 rigidly support subplate 22, which is attached to the movable cam assembly 25, which will be later discussed. This trolley mechanism permits the entire movable portion of the filament positioner I to roll freely back and forth upon shafts 20. Subplate 22 is secured to a crosshead member 26 shown in FIG. 7, by means of two clamp blocks 28, bolted to the crosshead, head, whose jaws are securely locked against the subplate by clamping bolts 29. Subplate 22 is provided with a pair of slots 31 (FIGS. 4 and 7) centered on the center line of clamping bolts 29, and sufficiently wide to allow clamping bolts 29 to slide through them. By loosening bolts 29, subplate 22 is permitted to slide linearly with respect to crosshead 26 and its clamping jaws 28, over a range of, e.g., 3 inches. The relative position of crosshead and subplate may be rigidly fixed by simply tightening clamping bolts 29. The purpose of this adjustment will be discussed later.

Motion of the subplate is induced by an actuator such as air cylinder 30, which is positioned along the center line of the filament positioner, and suitably bolted to base plate 18. The rod extending from the piston of air cylinder 30 is fastened to crosshead 26 by means of bolt 34. Together, the rod, crosshead, and clamp blocks constitute the powering member which transmits the force of cylinder 30 to the subplate 22. Cylinder 30 is double acting; it is capable of driving subplate 22 in either direction.

Turning to FIGS. 5 and 9, mounted atop subplate 22 is a cam assembly 25 including lower cam plate 35 and upper cam plate 17 Lower cam 35 is flat and on its upper surface bears a number of precision machined slots which fan out from the forward end thereof. Positioned above lower cam plate 35 is the upper cam plate 17 which bears on its lower surface precision machined slots 19 which precisely match the slots machined into lower cam 35. interposed between upper cam 17 and lower cam 35 are a plurality (e.g., 36) of elongated guide fingers 37. These fingers (e.g., precisely 0.050 inches in diameter) extend in a direction generally parallel to the length of the filament positioner apparatus. The rear tips of guide fingers 37 are provided with pivot pins 41, which extend in 'a direction perpendicular to the surface of base "plate 18. A block 36 (FIG. 5) is bolted by means of bolts 38 to base plate 18, and is provided with long pivot slot 43. Pivot pins 41 are positioned such that they fit into slot 43. The latter is sufficiently wide to allow all 36,pivot pins, with their associated elongated guide fingers, to rest side-by-side in contact with one another. Thus, guide fingers 37 are pivotally anchored in slot 43, which is firmly attached to the nonmovable base plate 18.

Referring to FIG. 8, each of guide fingers 37 has attached to it, at a precisely determined distance down its length, said distance being equal for each guide finger, a follower or drive pin 42. The latter are perpendicular to the surfaces of fiat earns 17 and 35, and extend in a direction both above and below guide fingers 37. Follower pins 42 are welded in milled slots in guide fingers l4 and plunge-milled to exact diameter to fit with extremely close tolerance into the corresponding slots l9 in the cam assembly 25. Thus, when earns 17 and 35 of the cam assembly 25 are moved back and forth in unison, guide fingers 37 spread apart on forward motion of said cams, and close on backward motion thereof.

As illustrated in FIGS. 5 and 8, each guide finger 37 is tipped with a filament guide 44. The filament guides 44 are interchangeable, i.e., can be removed from the tips of guide fingers 37 and replaced with other filament guides of different sizes. These guides serve to precisely position the wire or conductor filaments which are fed by the adjustable filament positioner apparatus into the laminating machine during manufacture of flat multiconductor cables. Needless to say, since precise positioning of the conductors is of the essence, the filament guide must precisely fit the size of wire conductor being used, in order to effect exact positioning of the wires. The fact that the wire guides are removable from guide fingers 37 enablcs the adjustable filament positioner to operate using a wide range of sizes of wire conductors, without necessitating changing of guide fingers 37. When it is desired to change the size of wire conductor, all that need be done is to interchange guides 44.

Turning again to FIG. 8, guides 44 are located in tapered holes 45 close to the tips of guide fingers 37. The location and size of this tapered hole is standard for all guide fingers and must be quite exact so that the distance from the center line of pivot pin 41 of each finger 37 to the exit edge 44a of guide 44 is precisely equal for all guide fingers. Guides 44 are machined from a standard precision casting. The tapered pin extension 44b of guide 44 and the length of its body are standard. The slot 44c for guiding the wire and the overall width of the guide will be unique for each size of wire conductor for which the guide finger is adapted. A family of filament guides 44, covering a variety of wire widths and diameters, is necessary. These will be readily interchangeable in the standard guide fingers 37.

Particularly noting FIG. 5, guide fingers 37 are sandwiched between upper cam 17 and lower cam 35. Drive pins 42 are inserted in their respective cam slots 19 and their pivot pins 41 inserted into close fitting pivot slot 43 in pivot pin block 36.

Lower cam plate 35 is secured to subplate 22 and connected to upper cam plate l7 by four guide posts 46 passing through guide bushings 48 which are inserted in the subplate 22 and lower cam plate 35 assembly. Guide posts 46 are shouldered and locked to upper cam plate 17 by nuts 50. The lower ends of guide posts 46 are also shouldered and threaded and activating plate 53 is fastened to the lower ends of guideposts 46 by means of nuts 52. Surrounding guide posts 46, and located between actuating plate 53 and guide bushings 48 are four compression springs 54. It can be seen that the forces exerted by compression springs 54 cause the cam plates to clamp tightly against guide fingers 37. Actuating plate 53 is bolted to a pull-type solenoid 56 by means of link 58 and bolt 60, which secures the armature. When solenoid 56 is energized, its armature travel is transmitted through actuating plate 53 to guide posts 46 and compression springs 54, lifting upper cam 17 away from lower cam 35 and guide fingers 37. This stroke should be approximately .005 inches. This effectively releases guide fingers 37 to pivot about pivot pins 41 when cams l7 and 35 are moved.

During the manufacture of a cable, when it is desired to alter the degree of the position of the tips of guide fingers 37, solenoid 56 is activated, freeing guide fingers 37 for pivotal motion. Upon release of the solenoid, guide fingers 37 can be tightly held in any given position which has been detennined by the action of the pitch spreader. This insures that when it is desired that the guide fingers be held fixed they will remain so.

One of the most important features of this device is its capability to govern the end points of the stroke of the cam. Also, it is desirable in this invention to control the velocity of cam movement.

Regarding the former objective, means is provided to fix the point of furthest advance of the cam assembly 25. This consists of threaded bolt 70 (FIGS. 4 and 10) which is screwed into threaded hole in a block 71 attached to subplate 22. Bolts 70 are parallel to precision shaft 20. As shown in FIG. 4, each forward block 21 is provided with a stop 72 positioned such that it will engage tip 73 of each bolt 70 when the movable cam assembly is moved sufficiently forward on its trolley structure. By varying the degree of rotation of each bolt 70, the point of furthest advance of the movable cam structure can be precisely governed. When bolts 70 are rotated clockwise, tip 73 extends forward to a greater degree than before rotation, and the forepoint of the forestroke is moved back. Conversely, when bolts 70 are rotated in a counterclockwise direction, the movable cam assembly 25 is permitted a greater degree of forward motion.

There still remains the problem of variably limiting the point of furthest backstroke of the movable cam assembly 25 of the pitch spreader.

The return, or backstroke, of the pitch spreader assembly is limited partly by the piston of air cylinder 30. This piston is always allowed to bottom on the back stroke.

The extreme backpoint of stroke can then be defined by loosening clamping bolts 29 and manually moving subplate 22 relative to crosshead 26. This necessarily alters the backpoint of stroke, since crosshead 26 is firmly fastened to the piston of air cylinder 30, and the piston is always bottomed at the same oint. P This back position can be precisely measured by micrometer screw 74 (FIG. 5) that is screwed into threaded hole 76 in micrometer block 78. Micrometer block 78 is securely bolted to base plate 18, and is thus not movable. Micrometer screw 74 is so positioned that it is free to engage zero screw 80, which is screwed into zero block 79 that is fixed to upper cam plate 17. When clamping screws 29 are loosened, releasing subplate 22 from clamping block 28 of the crosshead, the subplate can be manually moved forward and back with respect to the crosshead. Adjustment of the extreme rear point of backstroke is accomplished by bottoming the piston of air cylinder 30 in its rearmost position and loosening clamping bolts 29; micrometer screw 74 and zero screw 80 are then utilized in order to position subplate 22 in the precise position desired for the rearmost point of the stroke. The particular technique of operation of this feature will be discussed later. When the subplate 22, and hence the cam assembly, are positioned in there desired rearmost position of stroke,- clamping bolts 29 are then tightened, effecting a rigid connection between crosshead 26 and subplate 22. Thus the fore-andback limits of stroke are set.

The velocity of cam assembly motion is controlled accurately by cooperating hydrochecks 62. These are mounted in a back-to-back relationship to base plate 18 by means of blocks 64 and bolts 65. Each hydrocheck is also suitably connected to crosshead member 26 by means of threaded bolts 66. The hydrochecks form a closed circuit hydraulic system, and include control needle valves 68. By connecting these units in a reverse relationship, as shown in FIG. 4, one unit will control speed during the forward stroke of the pitch spreader and the other will control the speed during the return stroke. These devices are well known and commercially available.

The operation of the adjustable filament positioner will now be discussed. The first step in setting up this device for operation is to position the subplate 22 relative to the clamping block of crosshead 26 such that is is zeroed." To accomplish this, the operator first energizes solenoid 56. This unclamps guide fingers 37. Clamping blocks 28 are then released by loosening bolts 29. The operator then makes certain that the piston of air cylinder 30 has bottomed in its fully retracted position. The cam assembly is moved manually backward until the filament guides are as close together as they will go, e,g., 0.050 inch apart. The rigid relationship between clamping block 28 and subplate 22 is then reestablished by tightening clamping bolts 29. Micrometer screw 74 is then adjusted such that it reads zero. The operator rotates zero reference screw 80 until it contacts the end of micrometer screw 74. Zero screw 80 is then fixed in its zeroed reference position by tightening lock nut 82. The unit is now zeroed. This operation is performed in precisely the above manner, regardless of the degree of position change required for the production of the individual flat conductor cable about to be run off.

To achieve a definite filament pattern, it is also necessary to fix the ratio of velocity of cam movement to the velocity of the wire conductors being drawn into the laminating machine.

The velocity of entry of the conductor filaments into the laminating machine is controlled by present methods. The velocity of motion of the movable cam assembly 25 of the adjustable filament positioner is adjusted by changing the area of openings of the control orifices of hydrochecks 62. Smaller openings reduce velocity; larger openings increase it. It is notable that, because velocity in one direction is dependent on the status of only one hydrocheck, the forward and backward cam velocities can be independently controlled.

The foregoing discussion has been of a general qualitative character. It is useful to consider a specific example ofa setup of this machine to illustrate its advantages.

Assume that it is desired to make flat multiconductor cable which, as shown in FIG. 2, possesses variable conductor spacing along its length. Assume further that it is desired that the spacing between adjacent conductor filaments be equal, no matter what the degree of spacing is at any one point. The positioning of cam slots 19 is crucial for attaining such a precise object. The slots must be individually angled such that the sliding in them of drive pins 42, as the cam assembly is moved, causes the elongated guide fingers to spread such that the lateral distance, i.e., parallel to pivot slot 43, between each tip, remains equal at all times for all the tips. This equality is to be maintained regardless of how great the degree of spreading is at any particular moment.

To this end, mathematical formulas have been derived defining precisely the cam slot angle 9, the length of the stroke ofthe cam, and the transfer angles of the conductors as the pitch of the cable is varied. By careful control of the individual finger pin cam slot angles, combined with independent adjustment of cam positions relative to stroke, and accurate control of stroke and cam velocity, there is provided the means for infinite adjustment of the smaller and larger pitch of the cable from, for example 0.050 inches to 0.0200 inches for any cable complex, for example, up to 36 wires. Control of cam velocity permits accurate control of the transfer angle of the outer wire during a pitch spreading operation. Removable Where SN=Distance wire travels at a right angle to direction of wire flow.

N=Wire number A =Smal1er pitch A =Larger pitch With this parameter S available, and utilizing the geometry and notations of FIG. 12, the following formula defines the cam slot angle 0 required for any wire in a cable complex:

-Wena N: MWAX) (N-.5) (A -A The development of this formula is given below. It is a design formula which may be used to calculate the cam slot angle for any wire in a cable complex. As noted, a practical limit appears to be 36 wires. Utilizing suitable parameters for rp and rf, (see definitions below), the cam slot angle for the 18 wire would be 2637. All other cam slot angles will be smaller. However, since the formula is general, any other suitable set of angles may be determined.

The derivation of the formula for the cam slot angle is as follows:

Referring to FIG. 12

rFRadius of pitch spreader finger rp=Radius of finger drive pin Ax=Smaller pitch Ax'=Larger pitch S-=Distance wire travels to obtain either Ax or A S =Maximum S,

S,,=Distance finger pin travels S =Maximum S,

STR =Cam plate stroke required STR =MaXimum STR l =Cam slot length -Maximum Icy ,BN=Angle offinger to obtain A) or Ax 9 =Cam slot angle N=Wire Number h tan 0 Hence:

Substituting Equations (9) and (12) in Equation (2) yields:

i t-fiai id x) tan 6 In triangles OAL and OJK and triangles OGQ and OLM cos BNF and cos 5P rp T17 Thus:

-cos BNX)--rr(1--/1SIN a) and h =rp(1COS B )=rp(1w/1-SIN 6N) But S S l BNX Tf and fiN 7f m 8 2 tten Since triangles OAL and OJK and triangles OCQ and OLM are similar:

( v s s (N0.5) (A -A )frornEquation(1) D1 f NX f X X 11 r in SN??? (N 0-5) x" x) 1f the cam slots of cam plates 17 and 35 are configured according to formula (l4) given above, another mathematical relationship has been derived for determining the exact length of the stroke and the beginning and ending points of the stroke in order to produce cables with conductor spacings ranging between any given pair of distances, e.g., within the range of 0.050 inches to 0.200 inches. These formulas are derived as follows:

From equations (l4), (l1) and (l), and with reference to FIG. l2:

Therefore, from (3a) and (9) the required cam plate stroke sTR =s h where STR is the required cam plate stroke From the geometry of the elements illustrated in FIG. 12, it is apparent that the cam slot length may be expressed as follows: (16a) The formula is applied as follows:

When it is desired to produce a flat conductor cable system with a given set of conductor separations or pitches, formula (16) is employed to compute first the back limit on the stroke of the cams and the forward limit thereof. The forward limit is the stroke from zero position (e.g., 0.050 inches pitch) to the maximum spacing. The back point is the stroke from 0.50 to the minimum spacing. V v

The setup required for the particular cable to be manufactured is as follows. First, the machine is zeroed" as described above. The operator must then again energize solenoid 56, unclamping fingers 37. Clamping bolts 29 are loosened. The moveable cam assembly 25 is moved forward manually until bolts 70 contact stops 72. Lock nuts 75 of bolts 70 are then loosened. Micrometer screw 74 is then set until it reads the figure which has been computed for the extreme forward limit of the stroke desired. Bolts 70 are rotated in a clockwise direction until zero screw 80 contacts the end of micrometer screw 74. Lock nuts 75 of bolts 70 are then tightened, fixing the position of the bolts.

Micrometer screw 74 is then rotated counterclockwise, i.e., back, until it reads the figure which has been determined as the back limiting position of the desired stroke. The moveable cam assembly is then pushed back manually until zero screw 80 again contact the ends of micrometer screw 74. Clamping bolts 29 should thenbe tightened, reestablishing .he rigid relationship between the cam assembly and clamping block 28 of crosshead 26. Solenoid 56 is then deenergized, causing cam plates 17 and 35 to clamp the guide fingers 37. It is then necessary to install at the tips of guide fingers 37 wire guides 44, appropriate for the type of conductor or filament material being used.

The angle assumed by the filament across the base material depends on the ratio between the speed the filaments are drawn into the laminating machine and the cam velocity of the filament positioner. This angle, referred to as the transfer angle is shown in FIG. 2 as fl." Faster cam motion gives a more acute transfer angle, slower motion a less acute angle.

Where the cam slot pattern conforms to the earlier mathematical relationships, the transfer angle may be derived with reference to the geometry and notations of the vector diagram of FIG. 13. The following formulas define the forward distance travelled by any wire during the spread cycle, and the cam plate velocity required to obtain this distance. The derivation is as follows:

V =Forward or reverse velocity of cam plate V =Forward wire velocity V =Horizontal pin velocity V =Tangential pin velocity V -=Horizontal wire velocity at finger V =Tangential wire velocity V' =Vector sum V and V S =Forward travel of wire S =Horizontal travel of wire S =Tangential travel of wire S' =Vector sum S and S B,,=Angle traversed by finger rf=Finger radius rp=Pin radius Referring to FIG. 13:

V V tanG V V cos B =V tan GNCOSBN Thus V rflrpV tane cosfi mm: v cos N) +[%Vc TAN 9,, cos .11 STR =V t But N=S NhN (See FIG. 12

Thus SCN hN T Accordingly: CN N S COS 5N= w COS 5N N= W COS 5N h (19) SWN:VW (20) s -h SWt VWttN C TAN N COS 5N (21) ort-hr:

The vector sum of the parameters is as follows:

Accordingly, the actual forward distance travelled by any wire will be SwN N Thus, the transfer angle a will be:

SN where sCFg sN COTAN 0.,

Once a desired set of transfer angles is determined, the above relation can be used to compute the appropriate cam velocity for achieving such transfer angles.

Note, however, that the same result can be obtained, often more easily, by empirical testing of various cam velocities, until one yielding the desired transfer angle is found.

This example, with its specific computations, is to be interpreted as illustrative of the capabilities of this invention, and is not intended to be limiting in any sense.

This machine is intended to have utility wherever there is a need for varying with time the positions of flexible filaments in any process whatever. it is possible to apply this device, for example, in the weaving industry, where fiber filaments or strands are desired to be fed in a precisely positioned pattern into an interspersement of other strands offiber.

it is apparent that the drive of the adjustable filament positioner may be readily adjusted to provide, within limits, any range of filament spacing; further, the filament transfer angle" may be adjusted by altering cam velocity.

It is also apparent that this machine enables easy adjustment to compensate for minor errors in setting up the machine and for pitch errors introduced by the fact that when heated plastic material is bonded to the wire conductor filaments, it

often shrinks on cooling. Therefore, within a given range of filament positions, this machine has an extremely flexible capability of producing flat conductor cable whose conductor filaments possess variable patterns and position; and this variation is possible without substitution of the cam assembly of the apparatus. This latter capability is of particular importance when manufacturing fixed pitch flat conductor cable.

While a particular embodiment of the present invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

lclaim:

1. An apparatus for controllably altering the transverse spacing between a plurality of parallel filaments disposed in the same plane and moving in a direction generally parallel to their length, preparatory to affixing the filaments to a flexible sheet material, comprising:

a. a support structure;

b. a trolley mechanism slidably mounted on said support structure for movement along a predetermined path;

c. a cam assembly mounted on said trolley mechanism;

d. actuating means for moving said cam assembly;

e. a plurality of elongated guide fingers, each of which is pivotally connected atone end to the support structure, while its opposite end is adapted to engage a filament,

f. follower means extending between each of said guide fingers and said cam assembly such that the position of said cam assembly governs the positions of said guide fingers; and

g. stop means to limit the travel of said cam assembly.

2. An apparatus as in claim 1, in which there is additionally provided a velocity control means for governing the velocity of said cam assembly along its predetermined path of travel.

3. An apparatus as in claim 2, in which said velocity control means comprises an adjustable hydrocheck connected between said support structure and said cam assembly.

. 4. An apparat u sas in claim Lin wliich said stop means includes (l) a fixed stop means, and (2) an adjustable stop means; the latter comprising a micrometer fixed to the support structure, and a zero block which is fixed on said cam assembly, and which zero block has a zeroscrew threadedly engaged therein and positioned for alignment with said micrometer.

5. An apparatus as in claim 1, in which said cam assembly includes two parallel spaced cam plates, both having corresponding guide slots therein for slideably receiving said follower means.

6. An apparatus as in claim 5, wherein said two parallel spaced cam plates are relatively moveable in a direction perpendicular to the plane of said plates, and wherein solenoid means are provided to move one of said cam plates relative to the other plate.

7. An apparatus as in claim 1, further comprising a filament guide removably attached to each of said elongated guide fingers.

8. An apparatus for guiding at least one filament moving generally along the longitudinal axis thereof, preparatory to introducing said filament into a machine for performing an additional operation on said filament, comprising:

a. a support structure;

b. a trolley mechanism mounted on said support structure and including a plurality of bearing blocks moveable along an established path;

c. a cam assembly mounted on said bearing blocks, said cam assembly being of a planar configuration and having in at least one of its surfaces at least one cam slot;

d. actuating means for moving said cam assembly along the established path of the trolley mechanism;

e. at least one elongated guide finger, said guide finger pivotally mounted adjacent one end to said support structure, said guide finger bearing at a point intermediate its length a drive pin adapted to slideably engage said cam slot, said guide finger bearing on its opposite end a removably mounted filament guide;

f. first and second stop means to limit the travel of said cam assembly along the established path of the trolley mechanism; and

g. velocity control means to adjustably govern the velocity of said cam assembly.

9. An apparatus as in claim 8, wherein said cam assembly comprises two generally parallel spaced cam plates, said cam plates having registered cam slots therein.

EDL-JARD MEFLETCHER, JR. gAttesting Cffioer P UNITED STATES PATENT OFFICE CERTIFICATE OF CGRRTZCTWN Patent No. 3,615,066 Dated Invent0r(s) Walton Rainey It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 24, after one insert slot 1v Column 8, line 65, "S Maximum S should be we S Maximum S Column 9, line 3, (rp) a); (rph (S should be 2 2 2 (rp) (rp h +(s Column 10, line 73, "sec-6 should be sec. 6

Column ll, line 4, "0.50"

should be .050 '1- Column 11, line 34, "L6 should be *fl-"P" Signed and sealed this 23rd day of May @91 2,

ROBERT GOTTSGHALK Commissioner of Patents RM PO-105O (10-69) uSCOMM-DC 60376-P69 us. GOVERNMENT PRmTmG OFFMZE was o36a-a34 

2. An apparatus as in claim 1, in which there is additionally provided a velocity control means for governing the velocity of said cam assembly along its predetermined path of travel.
 3. An apparatus as in claim 2, in which said velocity control means comprises an adjustable hydrocheck connected between said support structure and said cam assembly.
 4. An apparatus as in claim 1, in which said stop means includes (1) a fixed stop means, and (2) an adjustable stop means; the latter comprising a micrometer fixed to the support structure, and a zero block which is fixed on said cam assembly, and which zero block has a zeroscrew threadedly engaged therein and positioned for alignment with said micrometer.
 5. An apparatus as in claim 1, in which said cam assembly includes two parallel spaced cam plates, both having corresponding guide slots therein for slideably receiving said follower means.
 6. An apparatus as in claim 5, wherein said two parallel spaced cam plates are relatively moveable in a direction perpendicular to the plane of said plates, and wherein solenoid means are provided to move one of said cam plates relative to the other plate.
 7. An apparatus as in claim 1, further comprising a filament guide removably attached to each of said elongated guide fingers.
 8. An apparatus for guiding at least one filament moving generally along the longitudinal axis thereof, preparatory to introducing said filament into a machine for performing an additional operation on said filament, comprising: a. a support structure; b. a trolley mechanism mounted on said support structure and including a plurality of bearing blocks moveable along an established path; c. a cam assembly mounted on said bearing blocks, said cam assembly being of a planar configuration and having in at least one of its surfaces at least one cam slot; d. actuating means for moving said cam assembly along the established path of the trolley mechanism; e. at least one elongated guide finger, said guide finger pivotally mounted adjacent one end to said support structure, said guide finger bearing at a point intermediate its length a drive pin adapted to slideably engage said cam slot, said guide finger bearing on its opposite end a removably mounted filament guide; f. first and second stop means to limit the travel of said cam assembly along the established path of the trolley mechanism; and g. velocity control means to adjustably govern the velocity of said cam assembly.
 9. An apparatus as in claim 8, wherein said cam assembly comprises two generally parallel spaced cam plates, said cam plates having registered cam slots therein. 